This invention relates to adjustable hangers used in suspending a ceiling wherein joists, from which the hangers depend, extend across the top of a room and tiles in the ceiling are carried in frames held by the hanger. This invention, more particularly, relates to such hangers in which the stationary part of the hanger comprises catches mounted to the joist at different levels and the movable part of the hanger, attaching to a frame carrying tiles, comprises balls or other enlargements spaced along a strand and fitting in the catches. This invention, even more particularly, relates to such hangers wherein the distance the catches are spaced vertically from one another is different than the balls or other enlargements are spaced along the strand thereby permitting adjustment in the distance the frame hangs from the joist by moving either (a) a different ball or other enlargement of the strand to the same catch or (b) the same ball or enlargement to a different catch.
One known technique for adjusting distance tiles carried in frames of suspended ceilings hang from joists uses wire attached to the joist for drawing up or letting down the frames. This prior technique, although quite simple, becomes awkward and imprecise when making small adjustments. Other approaches for adjusting the distance a hanger suspends a load appear in the following U.S. Pat. Nos. 1,606,289; 2,735,157; 2,936,988; 3,263,388; 3,495,796; 3,874,035; 3,995,823. None of these patents, however, describe an adjustable hanger like the hangers of this invention.
The hanger of U.S. Pat. No. 1,606,289, for example, describes a hanger in which the strand is stationary and embedded in concrete. The hanger of U.S. Pat. No. 2,735,157 has a movable strand for making adjustments but a single catch. U.S. Pat. No. 2,936,888 describes an adjustable fixture hanger in which a clamping screw is used for making adjustments. U.S. Pat. No. 3,263,388 shows ceiling tile installation in which the tile are supported in the ceiling and adjustment is limited to moving intermeshing stems. U.S. Pat. No. 3,495,796 discloses an adjustable hanger for suspended ceilings in which adjustment is with coaxial U-shaped members having a plurality of holes in their flanges. The lower member carrying a frame for the tiles may be slid relative the upper member which is fixed in the ceiling and the members pinned together through the holes in adjusting the height of the frame. U.S. Pat. No. 3,874,035 discloses a hanger clip attachment to an overhead flanged beam providing means for connecting hangers for suspended ceilings. U.S. Pat. No. 3,995,823 discloses an adjustable hanging device in which a C- or V-shaped clamps with flexible ears have holes through which a rod extends The height of the rod is adjusted when the ears are flexed so the rod can be moved up or down.